As well as measuring the amount of interactions (likes, comments, sound on/off) a video gets - or whether it's live or not - Facebook will be measuring 'percent completion'. Which means that videos that are watched through to the end will be deemed more relevant.

Facebook reckons that the longer you spend watching a video before scrolling on, the more interested other people will also be to watch it.

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"While we expect that most Pages will not see significant changes in distribution as a result of this update, longer videos that people spend time watching may see a slight increase in distribution," Abhishek Bapna a product manager and Seyoung Park, a research scientist, explained in a Facebook blog post .

"So people who find longer videos engaging may be able to discover more of them in News Feed.

"As a side effect, some shorter videos may see a slight dip in News Feed distribution."

The pair didn't specify exactly when the new change will come in, only that it will be rolled out "in the coming weeks".